This project will provide a genetic framework for analysis of chemical or radiation-induced mutations affecting the development and function of the mouse lens. Approximately 60 mutants affecting the mouse eye are maintained in various experimental mouse colonies but few of the mutants have been characterized genetically or biochemically. A selection of nine mouse eye mutants have been accumulated at the NIEHS. These mutants are being analyzed by complementation analysis and linkage tests to identify loci capable of mutating to produce aberrant eye phenotypes. These stocks will then be used to determine whether induced eye mutants represent additional loci at risk or remutation at previously defined loci. cDNA probes for each of the classes of mouse lens crystallins have been obtained from J. Piatigorsky, National Eye Institute, and are being used to screen inbred strains of mice for restriction polymorphisms which will permit mapping of the mouse crystallin genes. This information will be used to facilitate genetic analysis of the lens mutants and to identify those types of lens mutants which are likely to have defective crystallin genes. We have successfully developed surgical and electrophoretic techniques to permit the incorporation of lens tissue into the biochemical specific locus test being conducted by Dr. Susan Lewis at the Research Triangle Institute. The use of lens tissues contributes an additional 13 loci to the test and also provides for the detection of mutations which produce microphthalmias and/or cataracts.